wich m30 variety is the best?

[diogo]

I understand that the "Big Six" came in a huge variety of displacements ranging from 2.5 cc to 3.5 (and even 3.4 and 3.5 turbo) now what I wanted to know is wich one is the more suitable option for the E30.
I understand the 3.5 is the torquiest but it's slow revving (at least in stock form), the 3.0 is really revvy, don't know the 3.2 althought I'm watching this forum regardind this conversion from anotherr forum member and really liked what I saw from SA 333i specs.
If you guys could help me on this I would apreciate cause I'm in the process of buying an M30 engine and want to buy the right one.
Plus I hear that you coul later fit the itb's and 24v head from a M88 engine to it is that true too?

thx in advance


Diogo

[Jonsku]

Yes, the're quite a lot of different M30's out there.

I'd say the only sensible option is M30B34 (out of E28, E34 or E32, 218hp or 211hp). No idea wasting time with less powered options.

24v head can not be fitted easily, more sensible would be to find whole M88 or S38 engine.
ITB's can be fitted, yes, but they need different engine management etc etc so no easy route either.

[flawdaboi407]

Get a 89+ m30 from a 535 or 735. It has the oil pump and pan you need for the swap. The older engines have different oil pans that wont clear the steering rack. So you need to swap the pan... and the oil pump. The m30b35 is the best bang for your buck IMO, and it drops right in.

[chadthestampede]

Get a 89+ m30 from a 535 or 735. It has the oil pump and pan you need for the swap. The older engines have different oil pans that wont clear the steering rack. So you need to swap the pan... and the oil pump. The m30b35 is the best bang for your buck IMO, and it drops right in.

Get it just so you don't have to do all the wiring I have to do with a b32. b35's use motronic 1.3 for which you can use the m20 wiring harness if you have to.

[euroshark]

Ireland Engineering has just introduced new high compression M10 pistons in sizes up to 90mm, making them the perfect choice for a hot 3.0 or 3.2 liter. They are affordable too, something like $320 for 4 of them. The M30 is peculiar in that you can get very close to the same power from a 3.2 as you can from a 3.4, with just a little less torque and slightly different curve. The reality is that you don't need all of the extra torque when the engine is going into an E30. Even the stock US spec 3.2 made 195ft/lbs vs the US B34 that made 215ft/lbs, but with the same compression and cam they only made 1hp less.

I'd have to agree that bang for your buck is probably best with a B35, especially if it already has the E32/E34 oil pan and pump (though changing them out is very simple and easy - I did it with the motor hanging from the hoist). Something more exotic would be cooler though, like a high compression 3.2 with a hot cam and headers, maybe megasquirt or something. For overall desirability, I'd have to say that an M90 (early big bore, short stroke euro 3.5) or a euro B34 take the win. They are totally different animals than the B35, they seem to be sportier even though on paper they make very similar numbers. The delivery of the power and torque is just very different.

[george graves]

M30B35 - but with that said, if I had to do it again, I'd think about a euro L-block. But I might have problems passing smog.

[Funkmasta]

Noting that you are from Portugal, I would source a high compression b34 and run with it. Or, since you have a later car, if you get a motor that runs the later motronic, your life could be a lot easier.

[funcrew]

Ireland Engineering was selling Euro "L" M30's & claimed that when combined with US-spec crank, produced approx 3.7L

http://store.nexternal.com/shared/StoreFront/default.asp?CS=ireland&StoreType=BtoC&Count1=158672511&Count2=75812935

Does anybody know the particulars of this combo? Is that how Metric Mechanic puts together their 3.7L crate engines?

[euroshark]

That is correct, the "L block" or M90 has a bore of 93.355mm (vs the B34 which is 92mm), and when coupled with the US spec 86mm stroke crank and rods (vs the M90s 84mm stroke) will produce around 3.65 to 3.7 liters. It's not that simple though, from what I have read approximately 2 to 3mm needs to be shaved off of the top of the M90 pistons so that they do not protrude from the top of the block at the top of their stroke... Or you can go with some custom pistons if you have the dough.

IEs stroker kit comes with new crank and rods but they are not BMW pieces and they are not forged. Metric Mechanic might use S38 cranks but I am not sure about that... They could be cast replacements too.

[Jean]

Ireland Engineering has just introduced new high compression M10 pistons in sizes up to 90mm, making them the perfect choice for a hot 3.0 or 3.2 liter. They are affordable too, something like $320 for 4 of them. The M30 is peculiar in that you can get very close to the same power from a 3.2 as you can from a 3.4, with just a little less torque and slightly different curve. The reality is that you don't need all of the extra torque when the engine is going into an E30. Even the stock US spec 3.2 made 195ft/lbs vs the US B34 that made 215ft/lbs, but with the same compression and cam they only made 1hp less.

I'd have to agree that bang for your buck is probably best with a B35, especially if it already has the E32/E34 oil pan and pump (though changing them out is very simple and easy - I did it with the motor hanging from the hoist). Something more exotic would be cooler though, like a high compression 3.2 with a hot cam and headers, maybe megasquirt or something. For overall desirability, I'd have to say that an M90 (early big bore, short stroke euro 3.5) or a euro B34 take the win. They are totally different animals than the B35, they seem to be sportier even though on paper they make very similar numbers. The delivery of the power and torque is just very different.

Hmmm, maybe I'll get that m10 bottom end rebuild after all haha.

[atan88]

Ireland Engineering was selling Euro "L" M30's & claimed that when combined with US-spec crank, produced approx 3.7L

http://store.nexternal.com/shared/StoreFront/default.asp?CS=ireland&StoreType=BtoC&Count1=158672511&Count2=75812935

Does anybody know the particulars of this combo? Is that how Metric Mechanic puts together their 3.7L crate engines?

Same motor I have in my E9 coupe